Device for converting liquid fuel to micron size droplets



Feb. 3, 1970 H. GOODNIGHT ET AL 3,493,131

DEVICE FUR CONVERTING LIQUID FUEL To MICRON SIZE DROPLETS Filed Mar ch 18, 1968 IN VENTORS HE RSHEL GOODW/GHT JOHN SMITH Z/NK ROBERT D. REED ATTORNEY United States Patent 3,493,181 DEVICE FOR CONVERTING LIQUID FUEL T0 MICRON SIZE DROPLETS Hershel Goodnight, John Smith Zink, and Robert D. Reed, Tulsa, Okla., assignors to John Zink Company, Tulsa, Okla, a corporation of Delaware Filed Mar. 18, 1968, Ser. No. 713,952 Int. Cl. F23d 13/36, 13/40; Bb 7/04 US. Cl. 239419.3 2 Claims ABSTRACT OF THE DISCLOSURE A nozzle structure for projecting liquid fuel for cornbustion thereof as a mist of micron size droplets. The energy of the atomizing medium and the energy of the liquid fuel impinging against portions of the nozzle are utilized to intermingle the liquid fuel with the atomizing medium prior to escape through the discharge ports of the nozzle.

The present invention relates to a device for converting liquid fuel into a mist of separate and distinct droplets of a micron size range and for projecting the mist to provide fuel having improved combustion characteristics.

It is known in the art to convert liquid fuel into small and separate droplets and numerous types of nozzles have been employed for this purpose. In such prior devices steam in admitted to the presence of oil but only the energy of the steam is utilized for forcing a mixture of the oil and the steam. An object of the invention is to provide a device wherein the energy of the gaseous medium and the energy resulting from impacting of the liquid fuel against surfaces of the device both contribute to the production of an emulsion of the fuel and the gaseous medium which is then projected as a mist of micron size droplets.

An object of the invention is to provide a device into which liquid fuel is supplied along with a gaseous medium under pressure such as steam and the atomizing medium is guided through passages of reduced areas where the liquid fuel is released and the low pressure areas de veloped by the accelerated gaseous medium draws the liquid fuel into impact engagement with surfaces of the device where liquid fuel spreads and thoroughly intermingles with the gaseous medium.

Other objects and features of the invention will be appreciated and become apparent as the present disclosure proceeds and upon consideration of the following detailed description taken in conjunction with the accompanying drawing wherein exemplary embodiment of the invention is disclosed.

In the drawing:

FIG. 1 is a side elevational view of a nozzle device embodying the invention.

FIG. 2 is a longitudinal sectional view taken on the line 2-2 of FIG. 1.

FIG. 3 is a similar view on a larger scale and showing the structure for supplying liquid fuel into the device.

FIG. 4 is a transverse sectional view taken on the line 4-4 of FIG. 2.

FIG. 5 is an elevational view of the downstream end of the device.

Structure for converting liquid fuel into droplets of small size includes a tip member 10 which forms the downstream end portion of the nozzle structure. An enlarged intermediate portion 11 has substantially flat faces 12 as best shown in FIGS. 4 and 5 so that the tip may be threaded into a tubular conduit 14. The tip member 10 is hollow and has a generally cylindrical shaped interior surface 16. A plurality of ports 17 in the forward portion are circumferentially spaced from each other and the axes of these ports diverge from each other in proceeding toward the downstream end of the device.

A pipe 21 extends into the tip members as shown in FIGS. 2 and 3. The pipe 21 is a smaller diameter than the surface 16 and an annular passage 22 is thereby provided between the exterior of the pipe 21 and the interior of the tip member 10. A head member 23 of the larger crosssectional area than the exterior of the pipe 21 is carried by the downstream end thereof. The head 23 is provided with substantially fiat exterior surfaces 26, as shown in FIG. 4. The pipe 21 and the head 23 may be supported Within the tip member 10 in any suitable manner so that the head member 23 is substantially symetrically spaced from the inner surface 16.

Liquid fuel is supplied under pressure into the pipe 21 and passes into the head 23. A plurality of radially disposed orifices 28 extend from the interior of the head member 23 and the exit ends of the orifices 28 terminate flush with the respective fiat surfaces 26. An atomizing medium such as steam is supplied into the conduit 14 and moves into the annular passage 22. The gaseous medium moves over the exterior of the head member 23. The atomizing medium moves through the spaces of restricted areas formed between such surface 26 and the inner cylindrical surface 16. The fiow area for the gaseous medium is thus reduced at a plurality of zones as it passes over the head 23. The atomizing medium accelerates in its movement through the restricted flow areas and the pressure in the zones indicated at 31 and at the exit ends of the respective orifices 28 is lower than the pressure upstream of the head 23 and lower than the pressure downstream of the head 23 and lower than the pressure at which the liquid fuel is supplied into the pipe 21. An appreciable pressure drop is thereby developed adjacent the exit end of each of the orifices 28-. The mechanical energy thus produced spreads the liquid fuel along the surface 16 where it intermingles with the gaseous medium to provide an emulsion of the liquid and the gaseous medium. The energy developed by the gaseous medium and the mechanical energy resulting from the impingement of the liquid fuel against surface 16 are both utilized in the production of the emulsion. The emulsion is discharged through the ports 17 as a mist of micron size liquid droplets.

While the invention has been described with regard to one type of nozzle structure it will be appreciated that changes may be made in the elements as well as the overall assembly. The number of surfaces 26 within the tip member may be reduced or increased with a corresponding change in the number of radially disposed orifices 28. Other structural arrangements may be provided for causing acceleration of the atomizing medium adjacent the exit end of the ports for liquid fuel. Such changes and others may be made without departing from the spirit and scope of the invention.

What we claim and desire to secure by Letters Patent is:

1. A device for projecting liquid fuel as a mist of micron size droplets comprising, a tip member having an interior cylindrical surface, said tip member having discharge ports through the downstream end thereof, a fuel supply pipe extending into said tip member and of smaller external dimensions than said cylindrical surface providing an annular passage between the exterior of pipe and said interior cylindrical surface, a head member carried by the downstream end of said pipe spaced from the downstream end of the tip member providing a chamber therein downstream of said head member, flat surfaces disposed in chordal positions defining the perimeter of said head member and providing restricted flow areas between the perimeter of the head member and said interior cylindrical surface, said head member having orifices providing communication from the interior of the pipe to the perimeter of said head member with exit ends of said orifices terminating flush with the respective flat surfaces for guiding the fuel towards said interior cylindrical surface, means for supplying a gaseous medium under pressure into said annular passage for movement through said restricted flow areas creating low pressure zones adjacent the exit ends of said orifices whereby the fuel moving through said orifices impacts against said interior cylindrical surface and said chamber accommodates expansion of the gaseous medium and the mixing of the fuel therewith prior to escape through said discharge ports.

2. A device for projecting liquid fuel as a mist of micron size droplets according to claim 1 wherein each orifice is disposed at right angles to the associated fiat surface.

References Cited UNITED STATES PATENTS 1,526,923 2/1925 Meden 239-4345 X 2,247,781 7/1944 Leiman 239425 X 1,516,408 11/1924 Schomann 239-431 2,933,259 4/1860 Raskin 239431 X FOREIGN PATENTS 1,287,342 2/ 1962 France.

SAMUEL F. COLEMAN, Primary Examiner US. Cl. X.R. 239-434.5 

